Double-barrel pump shotguns

ABSTRACT

An improved shotgun design that includes at least two barrels, a trigger assembly that allows for individual simultaneous firing of each barrel, a single magazine with parallel ammunition wells that each feed one barrel, and a single slide mechanism that actuates the loading/unloading mechanism and resets the firing mechanism for discharge of subsequent rounds.

REFERENCE TO RELATED PROVISIONAL APPLICATION

This application claims priority to provisional U.S. Application, Ser. No. 61/893,012, filed on Oct. 18, 2013, which is hereby incorporated by reference for all purposes.

BACKGROUND

The present disclosure relates generally to shotguns. In particular, double-barrel pump shotguns are described.

The Second Amendment to the United States Constitution guarantees American Citizens the right to bear arms. Firearms are a ubiquitous component of American culture and are used for many purposes, including hunting, recreational target shooting, home defense, and personal defense. Common types of firearms include handguns, rifles, assault rifles, and shotguns. Shotguns serve particularly vital peace keeping and defensive roles in law enforcement and military applications.

Known shotguns are not entirely satisfactory for the range of applications in which they are employed. For example, existing shotguns offer limited ammunition capacity. Conventional shotguns are often limited to single round or double round capacities. Further, spent shell casings must be removed from a shotgun barrel prior to loading and firing subsequent rounds.

In addition, although some conventional shotguns allow multi-round capacities, conventional shotguns are limited by maximum round capacity. Conventional multi-round capacities range from 2 rounds in a breach-load double-barrel shotgun to 32 rounds in a drum magazine shotgun. Drum magazines are often undesirable because the drum configuration is large and bulky.

Typically, rounds in a handgun magazine or high-powered rifle magazine are stacked in a staggered configuration. In other words, two columns of rounds are stacked side-by-side inside the magazine. Staggering the rounds in a staggered magazine essentially doubles the capacity of a linear stack magazine of identical dimension. Handgun and rifle rounds incorporate pointed or rounded tips that allow the round to exit the staggered magazine at an angle and to self-guide into the gun barrel.

Unlike handgun and rifle rounds that incorporate round or pointed tips, shotgun rounds are flat on the tip. Existing shotgun magazines have failed to incorporate a staggered configuration for existing shotgun rounds, primarily because the flat-tipped shotgun rounds cannot self-guide into the gun barrel. Thus, when flat-tipped shotgun rounds are pushed out of a staggered magazine, the flat-tipped rounds jam in the firing port causing the shotgun to malfunction.

Therefore, maximum round capacities of existing shotguns are limited by existing magazine configurations. Further, total capacities of existing magazine configurations are limited due to weight distribution and dimension limitations. Existing shotgun magazine configurations include under-barrel tubes, single-stack magazines, and drum magazines.

Conventional under-barrel tubes cannot extend past the shotgun barrel to which they are mated. Under-barrel tubes must not protrude past the exit port of the shotgun barrel because a protruding under-barrel tube would interfere with the trajectory of a round fired from the barrel. A longer under-barrel tube capable of holding more rounds would be awkward to maneuver and would inhibit the accuracy of the shotgun. Currently, a maximum round capacity of 4-16 rounds is feasible with conventional under-barrel tubes.

Additionally, existing single-stack magazines capacities are limited by length. Existing single-stack magazines mount beneath or above the shotgun barrel and are linear. In other words, rounds of ammunition are stacked directly above or below additional rounds and fed into the firing chamber in a linear fashion. The length of existing single-stack magazines must be limited to maintain balance and maneuverability with existing shotguns. A maximum round capacity of 10 rounds is feasible with existing single-stack magazines.

Moreover, conventional drum magazines are large, awkward, and fragile. Live rounds are configured in a coil inside conventional drum magazines. A traditional coil of live rounds feeds into the shotgun barrel through a firing chamber port. The coiled rounds require a large drum size to accommodate multiple rounds. Drum magazines are fragile and malfunction-prone. A maximum round capacity of 32 rounds is feasible with existing drum magazines. Although conventional drum magazines offer larger capacities, drum magazines are flawed due to the large size and unwieldy nature of the awkward drum.

Thus, there exists a need for shotguns that improve upon and advance the design of known shotguns. Particularly, there exists a need for double-barrel pump shotguns that incorporate side-by-side, staggered-stack magazines with large multi-round capacities. Examples of new and useful double-barrel pump shotguns relevant to the needs existing in the field are discussed below.

SUMMARY

The present disclosure is directed to an improved shotgun design. The improved shotgun includes at least two barrels, a trigger assembly that allows for individual or simultaneous firing of each barrel, a single magazine with parallel ammunition wells that each feed one barrel, and a single slide mechanism that actuates the loading/unloading mechanism and resets the firing mechanism for discharge of subsequent rounds.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a first example of a double-barrel pump shotgun.

FIG. 2 is a top overall view of the double-barrel pump shotgun shown in FIG. 1 depicting the shotgun disassembled.

FIG. 3A is a side cutaway view of the double-barrel pump shotgun shown in FIG. 1 depicting a chain drive trigger mechanism inside a lower receiver.

FIG. 3B is a top view of the double-barrel pump shotgun shown in FIG. 1 depicting the chain drive trigger mechanism shown in FIG. 3A in its paired configuration, with one trigger mechanism for each barrel.

FIGS. 4A and 4B are perspective views of one of the bolts from the double-barrel pump shotgun shown in FIG. 1.

FIG. 5 is a perspective view of the magazine from the double-barrel pump shotgun shown in FIG. 1.

DETAILED DESCRIPTION

The disclosed double-barrel pump shotguns will become better understood through review of the following detailed description in conjunction with the figures. The detailed description and figures provide merely examples of the various inventions described herein. Those skilled in the art will understand that the disclosed examples may be varied, modified, and altered without departing from the scope of the inventions described herein. Many variations are contemplated for different applications and design considerations; however, for the sake of brevity, each and every contemplated variation is not individually described in the following detailed description.

Throughout the following detailed description, a variety of double-barrel pump shotgun examples are provided. Related features in the examples may be identical, similar, or dissimilar in different examples. For the sake of brevity, related features will not be redundantly explained in each example. Instead, the use of related feature names will cue the reader that the feature with a related feature name may be similar to the related feature in an example explained previously. Features specific to a given example will be described in that particular example. The reader should understand that a given feature need not be the same or similar to the specific portrayal of a related feature in any given figure or example.

With reference to FIG. 1 a first example of a double-barrel pump shotgun, double-barrel pump shotgun 100, will now be described. Double-barrel pump shotgun 100 functions to dramatically increase the round capacity and effective firepower of existing shotguns. Additionally or alternatively, the 50-round magazine of double-barrel pump shotgun 100 can be loaded with #1 buckshot to facilitate or allow firing 800 thirty caliber projectiles down range in just over 20 seconds. Thus, the effective firepower of double-barrel pump shotgun 100 is greater than five M-60 machine guns firing concurrently in the same period of time.

Double-barrel pump shotgun 100 addresses many of the shortcomings existing with conventional shotguns. For example, double-barrel pump shotgun 100 incorporates a staggered-stack, side-by-side magazine with a 50-round capacity. Moreover, shotgun 100 facilitates or allows feeding flat-tipped shotgun rounds from a staggered magazine and eliminates the shortcomings of conventional shotguns.

By incorporating the staggered-stack, side-by-side magazine, shotgun 100 eliminates the magazine shortcomings of existing shotguns. The magazine of shotgun 100 mounts directly under the center of the receiver and eliminates any protrusion risk presented by conventional linear tube magazines. It offers significantly better capacity than a tubular magazine mounted underneath the barrel, which cannot exceed the barrel length, and cannot be removed to allow for quick swapping with a second, preloaded magazine. It offers a shorter length (in exchange for a slightly wider profile) compared with existing non-staggered linear magazines. Finally, compared to existing drum magazine designs, it offers greater mechanical robustness, resistance to adverse handling conditions, and a substantially slimmer profile.

Moreover, the stack configuration of the new magazine ensures shotgun 100 is balanced and stable. Placing the magazine in the center of the receiver just in front of the trigger and grip facilitates or allows carrying and maneuvering shotgun 100 conveniently and easily. Additionally, centering the magazine between the grip and fore-grip distributes the weight of double-barrel pump shotgun 100 and eliminates trigger arm fatigue.

As shown in FIGS. 1-5, double-barrel pump shotgun 100 includes an upper receiver 110, a lower receiver 112, an ejection port 114, a trigger 120, a first gear 121, a second gear 122, a first sprocket 123, a second sprocket 124, a grip 125, a first chain 127, a second chain 128, a magazine 130, a fore-grip 135, operating rods 140, a first bolt 143, a second bolt 144, a first rear sprocket 147, a second rear sprocket 146, a first rear gear 149, a second rear gear 148, a first barrel 150, a second barrel 155, a shroud 160, an end cap 162, a rear sight mount 170, a plate 175, a bolt stop 176, and a butt stock 180.

As can be seen in FIG. 1, upper receiver 110 comprises the upper half of shotgun 100. Upper receiver 110 is complimentarily configured with lower receiver 112 and cooperatively houses the internal mechanics of shotgun 100. Ideally, upper receiver 110 is constructed from hardened 4140 tool steel. However, the upper receiver may be comprised of any now known or later developed material suitable for housing internal mechanics of firearms, including, but not limited to, wood, metal, plastic, glass-filled Nylon 66, Zytel®), carbon fiber, or composites. Upper receiver 110 includes ejection ports 114.

As shown in FIGS. 1 and 2, ejection ports 114 facilitate or allow bilaterally ejecting spent or fired shotgun shells from double-barrel pump shotgun 100. In the FIG. 1 example, ejection ports 114 are configured laterally. In other examples, the ejection ports may be arranged in any configuration that facilitates or allows safely and effectively ejecting spent shells. Acceptable ejection port configurations include, but are not limited to, vertical, acute angled, and obtuse angled.

Lower receiver 112 comprises the lower half of shotgun 100. Lower receiver 112 is complimentarily configured with upper receiver 110 and cooperatively houses the internal mechanics of double-barrel pump shotgun 100. In the FIG. 1 example, lower receiver 112 is comprised of 30-percent glass-filled Nylon 66, or Zytel® brand material. In other examples the lower receiver may be comprised of any now known or later developed material suitable for housing internal mechanics of firearms. Suitable lower receiver materials include, but are not limited to, wood, metal, plastic, carbon fiber, or composites.

Upper receiver 110 and lower receiver 112 together combine to form the primary housing of shotgun 100. Into this combined primary housing are inserted the first barrel 150, second barrel 155, magazine 130, a trigger assembly comprised of trigger 120, first gear 121, second gear 122, first sprocket 123, second sprocket 124, grip 125, first chain 127, and second chain 128, first bolt 143, and second bolt 144, and bolt stop 176. Butt stock 180 is attached to the outside of the combined primary housing, along with rear sight mount 170 and plate 175. Operating rods 140 protrude into the combined primary housing and attach to the first bolt 143 and second bolt 144 to enable actuation of the bolts, comprising the action of the shotgun 100. The workings of the action will be described further below.

Also shown in FIGS. 1 and 2, grip 125 facilitates or allows controlling and manipulating shotgun 100. Grip 125 is anatomically shaped to facilitate or allow gripping by a human hand. Additionally or alternatively, the grip may include grip elements to increase or improve user comfort. Examples of acceptable grip elements include, but are not limited to, rough or textured surfaces, rubberized surfaces, finger ridges, and palm indentions. Grip 125 is preferably constructed from either molded plastic, shaped or carved wood mounted to a metal or plastic frame, or plastic or metal coated with a cushioning rubber grip surface. Grip 125 may, however, be constructed from any material suitably strong to withstand the forces generated by the recoil of the shotgun 100 during firing and during actuation of the action by sliding the fore-grip 135 fore and aft. Such materials include wood, metal, plastic, composites, or any suitably strong material now known or later developed.

Further considering FIG. 2, shotgun 100 can be rapidly disassembled into its component parts without tools in under 30 seconds by pressing two levers. Disassembly begins by removing the butt stock 180 by removing the stock lock pin 210, which is used to adjust the butt stock 180, and sliding the butt stock 180 off. This exposes disassembly lever 220 on the back of the upper receiver 110. By pressing down on the disassembly lever 220, the top of the upper receiver 110, plate 175 with the handle and rear sight mount 170, along with the bolt guide rails, will slide to the rear and off. Bolt stop 176 is removed by lifting it out vertically. Next, the vertical fore-grip 135 under the barrel is unlocked with the thumb actuated lever on the side of the grip shown in FIG. 2 and pulled to the rear. Both bolts 143 and 144 will drop free into the rear of the upper receiver 110, and may be removed. Front disassembly lever 230, located at the front of the barrels is then moved to the left, enabling removal of the block between the barrels, the slide action vertical fore-grip 135, the vertical grip mount, the slide action rods 140, and the barrel shroud 160.

Shotgun 100 can be reassembled by reversing the foregoing steps. In the example shown in FIGS. 1-3B, trigger 120 is configured in two identical halves as a side-by-side double trigger. Pulling one side of trigger 120 in turn fires a live round from its associated barrel of the double-barrel pump shotgun 100. By placing the two halves adjacent to each other, both sides of trigger 120 may be pulled simultaneously to fire a live round from both barrels simultaneously. The trigger 120 may alternatively be configured as a single trigger which fires one round from one barrel of the shotgun on a first pull, and one round from the second barrel of the shotgun on the second pull. In yet a further variation, the trigger 120 may be configured as a single trigger which fires both barrels of the double-barrel pump shotgun simultaneously.

FIG. 3A depicts the trigger and tire control mechanism for a single barrel and bolt. As shown most clearly in FIG. 3A, pulling trigger 120 moves a slide bar 310 that makes contact with first rear gear 149, which converts the sliding motion of the slide bar 310 into rotational motion. First rear gear 149 imparts rotational motion a first rear sprocket 147 via rear shaft 320, to which both first rear gear 149 and first rear sprocket 147 are affixed. This rotational motion is concurrently imparted to a first sprocket 123 by way of a first chain 127. First sprocket 123 imparts its rotational motion to first gear 121 via front shaft 330, to which first sprocket 123 and first gear 121 are affixed. Finally, first gear 121 is in physical contact with the firing mechanism in first bolt 143, actuating the mechanism and thereby firing a round of ammunition as trigger 120 is pulled.

For triggers 120 implemented as two adjacent halves capable of firing each barrel independently, the foregoing trigger and tire control mechanism is duplicated in mirrored fashion for a second bolt 144 and barrel. In particular slide bar 310, rear shaft 320, and front shaft 330 (shown in FIG. 3A as second front shaft 340) all independently move as their corresponding trigger 120 is pulled.

Turning to FIG. 3B, an overhead view is provided of the two mirrored trigger and fire control mechanisms, showing the identical first rear gear 149 and second rear gear 148, first rear sprocket 147 and second rear sprocket 146, first chain 127 and second chain 128, first sprocket 123 and second sprocket 124, and first gear 121 and second gear 122. Where trigger 120 is configured as a single trigger that fires both barrels simultaneously, the trigger and tire control mechanism will possess a single slide bar 310 that actuates a single rear gear 149, which in turn is affixed to a single rear shaft 320, to which are affixed first rear sprocket 147 and second rear sprocket 146. The single bar 310, rear gear 149, and rear shaft 320 thus impart motion from the pulled trigger 120 simultaneously to both mirrored fire control mechanisms.

FIGS. 4A and 4B show the components of a bolt 400, an example embodiment of first bolt 143 and second bolt 144. Bolt 400 includes an extractor plate 410, a control rod 420, a locking pin 430, firing pin 440, and firing pin sear 450. Extractor plate 410 catches upon a rim or groove built into the base of the case of a round of the appropriate ammunition, enabling the case to be extracted from the breech of the barrel associated with the bolt upon cycling the shotgun 100's action. Control rod 420, ideally located on the opposing side of the bolt 400 from the extractor plate 410, engages with an internal cam within the bolt 400 for raising or lowering the locking pin 430. Locking pin 430, when raised, fixes the bolt 400 in position at the breach of its associated barrel when a round of ammunition is chambered in the barrel so as to ensure a secure firing of the round. The control rod 420 also extends from the bolt 400, passes through the receiver housing the bolt 400 and attaches to the slide or fore-grip to enable cycling of the shotgun 100's action. Bolt 400 is preferably comprised of 4140 steel or “tool steel.” Alternatively, bolt 400 may be comprised of any now known or later developed material that is suitable for containing the breech pressures and recoil forces experienced during the firing of a round of ammunition. Examples of suitable bolt materials may include, but are not limited to, aluminum, titanium, cobalt, tungsten carbide, wood, plastic, ceramic, carbon fiber, and composites.

As described above in connection with FIGS. 1 to 3B, first gear 121 and second gear 122 contact and activate the firing mechanism in first bolt 143 and second bolt 144, respectively. Firing mechanism in example bolt 400 is comprised of the firing pin sear 450, which pressure applied thereupon via the fire control mechanism gear trips the spring-loaded firing pin 440, causing it to rapidly emerge from inside of bolt 400 and strike the primer of a round of ammunition, resulting in discharge of the shotgun 100. The internal firing pin mechanism and ejector mechanism in bolt 400 are well known in the art, and thus will not be discussed in detail. Any now known or later developed firing mechanism and ejector mechanism may be incorporated in the bolts. An example firing cycle of double-barrel pump shotgun 100 will be discussed in detail below.

In FIG. 5, the components of a magazine 500 are shown. Magazine 500 possesses a body 510 which is shaped to securely couple with lower receiver 112, which is in turn equipped with a latching mechanism to retain an inserted magazine 500 until unlatched. Such latching mechanisms are well-known in the art. Magazine 500 is configured as a staggered-stack, side-by-side magazine. Two ammunition wells 520 are created by the insertion of a partition 530, which splits the body 510 into the two ammunition wells 520. Into each ammunition well 520 is inserted an ammunition follower 540 and spring 550. The spring 550 contacts the follower 540 at one end, and the magazine bottom plate 560 at its opposite end. As ammunition is inserted into an ammunition well 520 it rests atop follower 540, which is depressed down into the ammunition well 520 and simultaneously compresses spring 550. Spring 550 thus imparts an increasing force against follower 540 and pushes the inserted ammunition to the mouth of the well 520, in position for loading by the shotgun 100's action. As discussed above, the staggered-stack magazine configuration is common in handguns and rifles. However, magazine 500 pairs two single staggered-stack magazines in a side-by-side configuration; each half of magazine 500 functions independently. Thus, magazine 500 facilitates or allows first barrel 150 and second barrel 155 to function independently.

In the example embodiment, magazine 500 ideally has a maximum capacity of 50 rounds. Alternatively, the magazine may be configured to hold fewer or more rounds. Essentially, the overall length and total weight of the fully loaded magazine will be limiting factors when determining the maximum capacity of the magazine. The components of magazine 510 are ideally made of a material that is lightweight yet strong, such as aluminum, plastic, Nylon 66, Zytel®, a composite, or any other suitable material capable of securely and rigidly holding the weight of ammunition contained therein.

As shown in FIGS. 1-4B, first barrel 150 and second barrel 155 are inserted into upper receiver 110 and lower receiver 112. The inner surface of upper receiver 110 and lower receiver 112 are tapered proximate first barrel 150 and second barrel 155 to facilitate or allow guiding rounds of ammunition exiting magazine 130 into first barrel 150 and into second barrel 155. As a round of ammunition exits magazine 130 due to motion of the bolt towards the breech of its associated barrel, the combination of the extractor plate 410 and control rod 420 on each bolt act in concert to center a round of ammunition as it feeds from the magazine 130 on the bolt face, which in turn aligns the round of ammunition with the axis of the bolt's associated barrel. As the round of ammunition is further pushed forward by the bolt, it meets the aforementioned tapered inner surfaces of upper receiver 110 and lower receiver 112. The combined effect of the extractor plate 410, control rod 420, and tapered inner surfaces acts as a funnel to guide the blunt front end of the round of ammunition into the breach end of the barrel, enabling smooth, consistent, and jam-free feeding.

In the FIGS. 1 and 2 example, first barrel 150 and second barrel 155 are comprised of steel. Specifically, the first and second barrels are comprised of 4140 steel or “tool steel.” Alternatively, the first barrel and the second barrel may be comprised of any now known or later developed material. Examples of suitable barrel materials include, but are not limited to, aluminum, titanium, cobalt, tungsten carbide, wood, plastic, ceramic, rubber, carbon fiber, composites, alone or in suitable combinations as appropriate to the materials employed.

As shown in FIGS. 1 and 2, operating rods 140 pass through lower receiver 112, connecting first bolt 143 and second bolt 144 with fore-grip 135. Operating rods 140 facilitate or allow shotgun 100's action to cycle between loaded and unloaded configurations. In other words, operating rods 140 cycle first bolt 143 and second bolt 144. Fore-grip 135 facilitates or allows a user to control and manipulate shotgun 100. Fore-grip 135 allows users to steady or aim the firing end of first barrel 150 and second barrel 155 and to pump or rack operating rods 140 to cycle first bolt 143 and second bolt 144.

In the FIG. 1 example, fore-grip 135 is a below-barrel vertical fore-grip. Alternatively, the fore-grip may be configured in any shape or form that facilitates or allows aiming and cycling the double-barrel pump shotgun. Acceptable fore-grip configurations include, but are not limited to, in-line, side-barrel horizontal, and above-barrel vertical. The fore-grip may also include elements to increase or improve user comfort. Examples of acceptable fore-grip elements include but are not limited to rough or textured surfaces, rubberized surfaces, finger ridges, and palm indentions.

In the FIG. 1 example, fore-grip 135 is comprised of 30-percent glass-filled Nylon 66, or Zytel®. In other examples, the fore-grip may be comprised of any now known or later developed material suitable for facilitating aiming and cycling the double-barrel pump shotgun. Suitable fore-grip materials include, but are not limited to, wood, metal, plastic, rubber, ceramic, carbon fiber, and composites.

As shown in FIGS. 1 and 2, a shroud 160 surrounds or protects first barrel 150 and second barrel 155. In the FIG. 1 example, shroud 160 is comprised of 30-percent glass-filled Nylon 66, or Zytel®. In other examples the shroud may be comprised of any now known or later developed material suitable for protecting the barrels. Suitable shroud materials include, but are not limited to, wood, metal, plastic, rubber, ceramic, carbon fiber, and composites. Additionally, the shroud serves an aesthetic purpose and may be configured in any aesthetically pleasing shape or form.

As shown most clearly in FIG. 2, end cap 162 is configured to cooperatively couple with shroud 160, first barrel 150, and second barrel 155. In fact, end cap 162 locks or maintains shroud 160 around first barrel 150 and second barrel 155. Moreover, end cap 162 acts as a stop to maintain fore-grip 135 and operating rods 140 in proper operating position (“racked”) when cycling double-barrel pump shotgun 100.

As shown in FIGS. 1 and 2, rear sight mount 170 mounts to upper receiver 110. In the FIG. 1 example, rear sight mount 170 is configured to facilitate or allow gripping by a human hand and allows mounting optical sighting elements. Alternatively, the sight mount may be configured with a peep sight or to accommodate any now known or later developed sighting element.

As can be seen in FIG. 2, plate 175 is configured to mount rear sight mount 170 to upper receiver 110. In the FIG. 2 example, plate 175 is comprised of 30-percent glass-filled Nylon 66 or Zytel®. In other examples, the plate may be comprised of any now known or later developed material suitable for mounting the rear sight mount to the upper receiver. Suitable plate materials include, but are not limited to, wood, metal, plastic, rubber, ceramic, carbon fiber, and composites.

As shown in FIGS. 1 and 2, butt stock 180 is cooperatively coupled with lower receiver 112. Butt stock 180 is anatomically configured to accommodate a human shoulder. Moreover, butt stock 180 is adjustable to make shotgun 100 more comfortable for a user to use and easier to control. Butt stock 180 is comprised of 30-percent glass-filled Nylon 66, or Zytel®. In other examples the butt stock may be comprised of any now known or later developed material suitable for facilitating user comfort and control of the shotgun. Suitable butt stock materials include, but are not limited to, wood, metal, plastic, rubber, ceramic, carbon fiber, and composites.

Many of the above components of double-barrel pump shotgun 100 are identical on opposite sides. In other words, many components on one-half of double-barrel pump shotgun 100 are a mirror image of the same components on the other one-half. It is also contemplated that single components of the double-barrel pump shotgun may be utilized to comprise a single-barrel pump shotgun. Indeed, a single staggered-stack magazine with 25-round capacity may be combined with other components listed above to comprise a robust, single-barrel pump shotgun with firepower and balance superior to existing pump shotguns.

With reference to FIGS. 1-5, the tiring cycle of double-barrel pump shotgun 100 will now be described. First, with live rounds loaded in magazine 130, magazine 130 is inserted in lower receiver 112. Racking fore-grip 135 from a first position distal lower receiver 112 to a stop position proximate lower receiver 112 also moves the attached operating rods 140. Concurrently, operating rods 140 cycle the attached first bolt 143 and second bolt 144. As the fore-grip 135 is moved rearward towards the lower receiver 112, the operating rods 140 first extend into their associated bolts, actuating their internal cams which in turn lowers the associated locking pins. This frees the bolts to be moved rearward by the operating rods 140, as they continue to travel rearward with the fore-grip 135. When fore-grip 135 reaches its rear-most stop position, first bolt 143 and second bolt 144 simultaneously eject any spent shell casings from the firing chamber out of ejection ports 114.

Next, the fore-grip 135 is moved back away from lower receiver 112 towards its forward stop. This in turn causes the operating rods 140 to pull first bolt 143 and second bolt 144 back towards the breach of each associated barrel. First bolt 143 and second bolt 144 simultaneously strip new, live rounds out of magazine 130 into first barrel 150 and second barrel 155, respectively. As the new rounds slide forward, they are pushed up by a combination of the magazine followers 540 and associated springs 550, and the tapered shape of the lower receiver 112. The rounds come into contact with their respective bolts' extractor plate 410 and the control rod opposing the extractor plate 410, which in combination serve to center the new rounds in line with the axis of each bolt's respective barrel, thereby ensuring smooth and accurate feeding of the new round. As fore-grip 135 is returned to the first position, first bolt 143 and second bolt 144 simultaneously complete loading the live rounds into first barrel 150 and second barrel 155, and cock the firing mechanism in each bolt. Following making contact with breaches of their respective barrels, final forward travel of the fore-grip 135 actuates the cam inside each bolt, which causes each bolt's respective locking pin to raise, thereby securing the bolts from rearward movement and making the shotgun 100 ready to fire.

A user may discharge the shotgun 100 by electing to pull one half of trigger 120 initially then the other half of trigger 120 subsequently, or both halves of trigger 120 simultaneously. Pulling trigger 120 fires rounds from first barrel 150 and second barrel 155. Following firing, cycling of fore-grip 135 as described in the foregoing repeats the above extraction, ejection, and loading cycle, rendering double-barrel pump shotgun 100 again capable of firing two new live rounds. This cycle may be repeated sequentially until all rounds in the magazine have been fired.

The disclosure above encompasses multiple distinct inventions with independent utility. While each of these inventions has been disclosed in a particular form, the specific embodiments disclosed and illustrated above are not to be considered in a limiting sense as numerous variations are possible. The subject matter of the inventions includes all novel and non-obvious combinations and subcombinations of the various elements, features, functions and/or properties disclosed above and inherent to those skilled in the art pertaining to such inventions. Where the disclosure or subsequently filed claims recite “a” element, “a first” element, or any such equivalent term, the disclosure or claims should be understood to incorporate one or more such elements, neither requiring nor excluding two or more such elements.

Applicant(s) reserves the right to submit claims directed to combinations and subcombinations of the disclosed inventions that are believed to be novel and non-obvious. Inventions embodied in other combinations and subcombinations of features, functions, elements and/or properties may be claimed through amendment of those claims or presentation of new claims in the present application or in a related application. Such amended or new claims, whether they are directed to the same invention or a different invention and whether they are different, broader, narrower or equal in scope to the original claims, are to be considered within the subject matter of the inventions described herein. 

1. A shotgun, comprising: a plurality of barrels; a plurality of bolts, where each one of said bolts is associated with one of said plurality of barrels; and each one of said bolts possesses a firing mechanism; a slide that is operably connected to said plurality of bolts so as to enable cycling of all of said plurality of bolts simultaneously; a magazine comprising a plurality of ammunition wells, where each one of said plurality of ammunition wells is associated with one of said plurality of barrels; and each one of said plurality of ammunition wells is positioned so as to allow feeding of ammunition inserted therein into its associated barrel by the bolt associated with the associated barrel; and a plurality of triggers configured so that each one of said triggers is associated with one of said plurality of bolts; and each one of said triggers can be independently actuated so as to release the firing pin of its associated bolt.
 2. The shotgun of claim 1, further comprising a receiver wherein said receiver houses the plurality of bolts, and into which the plurality of barrels and plurality of magazines are inserted.
 3. The shotgun of claim 2, wherein each of said barrels possesses a breach end capable of receiving a round of ammunition that is inserted into said receiver; each of said plurality of bolts possesses a face that contacts the base of said round of ammunition to be chambered, said face having two protrusions disposed on opposite sides of the face so as to align said shell with said breach end of said barrel; and said receiver further comprises an upper receiver portion and a lower receiver portion, where said upper and lower receiver portions have tapered inner surfaces proximate to the end of said plurality of barrels that is inserted into said receiver.
 4. The shotgun of claim 1, wherein said plurality of triggers are physically arranged so that all of said triggers can be actuated simultaneously.
 5. The shotgun of claim 1, wherein each of said plurality of triggers is operably connected to its associated bolt through a chain drive.
 6. The shotgun of claim 1, wherein said magazine ammunition wells store inserted rounds of ammunition in a stacked configuration.
 7. The shotgun of claim 6, wherein said magazine ammunition wells further store inserted rounds of ammunition in a staggered configuration.
 8. The shotgun of claim of claim 1, further comprising a grip attached to said slide to facilitate operating said slide.
 9. A shotgun, comprising: a shoulder stock; two barrels, each capable of receiving a round of ammunition; two bolts, each one of said two bolts paired to one of said two barrels and positioned so as to hold said round of ammunition into the end of said barrel, and possessing a firing mechanism for discharging said round of ammunition; a magazine capable of holding a plurality of rounds of ammunition; a foregrip disposed below said two barrels so as to slide axially relative to said barrels; one or more pushrods connected to said foregrip and said bolts, and positioned so as to move said bolts in response to sliding said foregrip, said movement allowing said bolt to insert and remove said round of ammunition into said barrel; and a housing wherein said shoulder stock is attached; said two bolts are enclosed and positioned so as to facilitate loading and unloading of said plurality of rounds of ammunition into the ends of said two barrels in response to sliding said foregrip; said barrels are inserted so as to allow said two bolts to load and unload said rounds of ammunition into the ends of said two barrels; and said magazine is inserted so as to hold said rounds of ammunition held therein between said two bolts and two barrels in a position that allows said bolts to transfer said rounds of ammunition into the ends of said two barrels.
 10. The shotgun of claim 9, further comprising a trigger mechanically linked to each of said two bolts so as to cause said firing mechanism in each of said two bolts to discharge said rounds of ammunition simultaneously.
 11. The shotgun of claim 10, wherein said mechanical link is comprised of a chain and at least two sprockets.
 12. The shotgun of claim 9, further comprising two triggers, each of said two triggers mechanically linked to one each of said two bolts so as to cause said firing mechanism in said linked bolt to discharge its associated round of ammunition.
 13. The shotgun of claim 12, wherein said two triggers are arranged so as to facilitate actuating both triggers simultaneously.
 14. The shotgun of claim 13, wherein said mechanical linkages are comprised of a plurality of chains and sprockets.
 15. The shotgun of claim 9, wherein each of said two bolts possesses an extractor positioned opposite to said pushrod, said extractor and pushrod arranged so as to center a round of ammunition to be loaded into the barrel associated with said bolt along the center axis of said barrel; and said housing further comprises an upper receiver and a lower receiver, with each of said upper receiver and lower receiver having a tapered inner surface proximate to the end of said barrels that are inserted into said housing, said tapered inner surfaces positioned so as to guide a round of ammunition to be loaded into either of said barrels along the center axis of said barrel.
 16. The shotgun of claim 9, wherein said magazine possesses a partition that divides said magazine into two ammunition wells, with each of said ammunition wells associated with one of said two barrels.
 17. The shotgun of claim 16, wherein each of said ammunition wells holds said rounds of ammunition in a stacked configuration.
 18. The shotgun of claim 17, wherein each of said ammunition wells holds said rounds of ammunition in a staggered stacked configuration.
 19. The shotgun of claim 9, further comprising a trigger mechanically linked to each of said two bolts so as to cause said firing mechanism in each of said two bolts to discharge said rounds of ammunition sequentially, with one round discharged for each actuation of said trigger.
 20. A shotgun, comprising: an adjustable shoulder stock; two barrels, each capable of receiving a round of ammunition; two bolts, each one of said two bolts paired to one of said two barrels and positioned so as to hold said round of ammunition into the end of said barrel, possessing a firing mechanism for discharging said round of ammunition, and two oppositely disposed protrusions arranged so as to align said round of ammunition with the center axis of said barrel; a magazine with two independent wells, each associated with one of the said two barrels and capable of holding a plurality of rounds of ammunition; a foregrip disposed below said two barrels so as to slide axially relative to said barrels; one or more pushrods connected to said foregrip and said bolts, and positioned so as to move said bolts in response to sliding said foregrip, said movement allowing said bolt to insert and remove said round of ammunition into said barrel; and a housing comprised of an upper and lower receiver, wherein said shoulder stock is attached; said two bolts are enclosed and positioned so as to facilitate loading and unloading of said plurality of rounds of ammunition into the ends of said two barrels in response to sliding said foregrip; said barrels are inserted so as to allow said two bolts to load and unload said rounds of ammunition into the ends of said two barrels; said upper and lower receiver have inner surfaces that are tapered towards the portion of said two barrels that is inserted into said housing so as to align a round of ammunition inserted into either of said two barrels with the center axis of said barrel; and said magazine is inserted so as to hold said rounds of ammunition held therein between said two bolts and two barrels in a position that allows said bolts to transfer said rounds of ammunition into the ends of said two barrels; and two latch levers disposed to enable disassembly of the shotgun. 